Why is Walter baffled that their attack failed in the Portal Shipment Lane?

Question

In the episode "An Origin Story" Walter, Peter and Olivia try to attack the future using one of the Portals they opened to transfer stuff in the past. Now Walter assumes that the attack they performed would create havok for years but then are baffled that a new portal was opened almost instantly. In the question found here it is explained why their attack "failed" which is the solution I personally gave to why it failed. My question is

-How could Walter, with the amazing mind he possesses could be baffled by something with such a simple explanation? Let's their attack was so devastating that it took 2000 years to resolve. After fixing everything they could again send something in the same time and space as they were originally planning thus the new instantaneous portal.

Answer 1

I think it was partly emotional. They had invested a lot of effort into that strategy, so he would have been hoping for some tangible payoff. His hopes were dashed, and brilliance doesn't remove emotions.

I also assumed that he expected to have disrupted the nature of the time travel tech, such as making that time and space a no-go zone. Or, even if the Observers knew hundreds of years in advance that the first shipment would be destroyed, they might have had limited resources and not been able to resend to there.

However, the Observers recovered immediately, showing no real signs of being inconvenienced. So, a lot of work, and a lot of hope, was for nothing at all.